Circuit interrupter



Patented Oct. 30, 1928.

; eeann UNITED STATES PATENT OFFICE.

JOSEPH w. LEGG, or WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO wnsrmenonsnELECTRIC & MANUFACTURING COMPANY, A oonrona'rron or PENNSYLVANIA.

CIRCUIT INTERRUPTER.

Application filed December 21, 1920. Serial No. 432,321.

One object of my invention is to providemagnetic flux-forming means forclosing a circuit interrupter and for holding theinterrupter closed andmeans for so reducing the said flux as to open the interrupter inresponse to certain circuit conditions and for preventing there-establishment of the flux to prevent the closing of the interrupterso long as said circuit conditions exist Another object of my inventionis to provide an exceedingly simple and effective apparatus that shallbe adapted to open a circuit in response to abnormal circuit conditionsand that shall prevent the closing of the circuit until normal circuitconditions arc'restored.

Heretofore, it has been usual to open a circuit in response to abnormalcircuit conditions and to prevent the reclosing of the circuit untilsuch conditions no-longer prevail but the means for so doing has usuallyinvolved the use of quite a number of interdependent switches andrelays. Several rela tively complicated and expensive systems of theabove general character have been pro posed, certain of which haverequired considerable special design.

In practicing my invention. 1 provide means whereby a switch or switchesof stand ard, or of substantially standard, form may be readily adaptedto function singly or col-o lectively to open a circuit in response topredetermined circuit conditions and to prevent the reclosure thereofduring the continuance of such conditions. By my invention,a singleswitch of the so-called standard character, may be constructed by themere rearrange.

ment of its electromagnet-coils or windings to function in the abovedescribed manner or a plurality of such switches may be constructed andrelated to effect the desired results.

Figure 1 of the accompanying drawing is a partially structural andpartially diagrammatic View of an electrical system and apparatusembodying my invention.

Fig. 2 is av wiring or circuit diagram of the system shown in Fig. 1.

As shown in Figs. 1 and 2, a system embodying my invention comprises, ingeneral, supply and return conductors land 2, respectiveis connected.across the lines ly, a. main circuit interrupter 3, and an auxiliarycircuit interrupter 4.

The main interrupter 3 may be of any suitable type, such as those havingautomatically reclosing features.

The auxiliary circuit interrupter 1, that may be suitably supported,as'on a switchboard panel 8, comprises a. terminal connector 9, ablowout coil 10, a stationary contact memis pivoted, by a pin 13, tothcoutcr end of an arm 14. The arm 14.- is pivoted, by a pin 15, to theouter end of a projection .16 on a bracket 17 that is secured to thepanel 8. A spring 18 is disposed between lugs 19 and 20,constitutingparts of the movable contact member 12 and the aria-14,respectively, and serves to give a wiping contact between the contactmembers 11 and 12. y i

. Current from the supply conductor 1 passes through the interrupter 8,the terminal connector 9, the blowout coil 10, the contact members 11and 12 and through a flexible connee-tor 21 that is connected betweenthe movable cont-act member 12 and a terminal connector 22. p

The arm 14 is provided with a recess 23 adapting the arm to fit over theouter end of a core member 24 of an electromagnetic device 25 that issupported on the bracket 17 and, further, comprises an energizing coil26 that 1 and 2 from a terminal connector 27, on the stationary contactmember 11, through a resistor 60.

As shown in Figs. 1 and 2, a coil is disposed on thecore member 2a ofthe switch 1 in series with the supply line 1., the blowout coil 10 andthe contact members 11 and 12. A coil 56 of few turns is connected, byconductors 57 and 58 through a resistor 59, to be in series with theline 1, when the interrupter is open.

Upon the occurrence of an overload, the flux of the shunt coil 26 willbe reduced or nullified by the series coil 55. and the switch will bethereby opened. After this opera-- tion, the switch will not close untilthe line current is reduced to normal or, in other words, until thecurrent through the resistor 59 and the coil 56 is so reduced as. topermit the coil 26to close the switch.

While I have shown and described aparticular form of my invention,changes may be effected therein Without departing from ber11 and a.movable contact member 12 that the spirit and scope thereof, as setforth in the appended claims.

I claim as my invention:

1. In an automatic reelosing circuit in terrn 'iter system, thecombination with a supply circuit, a load circuit, and a circuitinterrupter therebetween, 0t means for controlling the operation of thecircuit interrupter comprising a single magnetic circuit and a pluralityof magnet coils for energizing said magnetic circuit. one of said coilsbeing permanently connected in parallel relation to the supply circuitto be energized only in response to the potential thereof, another otsaid coils being permanently connected in series with the supply circuitto be energized only in response to the rate of current trayersalbetween the supply circuit and the load circuit and so disposed as toenergize the magnetic circuit differentially with respect to thefirst-mentioned coil, and a third one of said coils being connected inparallel relation to the circuit interrupter and so disposed as toenergize the magnetic circuit ditl'erentiallywith respect to thefirst-mentioned coil when the circuit interrupter is open.

2. An automatic reclosing circuit interrupter system comprising astationary contact member, a movable contact member, an electric circuithaving two portions connected, respectively, to the two contact members,

a magnetizable armature member for actuating the movable contact member,means for conducting current between the two portions of the circuitwhen the movable contact memher is out of engagement with the stationarycontact member, a single magnetic circuit including the armature member,a magnet coil energized only in accordance with the potential of one ofthe portions of the electric circuit and coo erating with the magneticcircuit to tend to actuate the armatiu'e memher to, and to maintain itin, its closed position, a second magnet coil energized in accordaucewith the rate of current traversal between the two portions of thecircuit when the stationary contact member and the mov able contactmember ire in ensz'agen'ient and ditt'erentially opposed to thefirst-mentioned magnet coil in relation to the magnetic circuit, and athird magnet coil energized only in accordance with the rate of currenttravorsal between the two portions of the circuit when the stationarycontact member and the movable contact member are out of enga ement anddili'erentially opposed to the firstmentioned magnet coil in relation tothe magnetic circuit.

In testimony whereof, I have hereunto sub scribed my name this 13th dayof December, 1920.

JOSEPH WV. LEGG.

